The invention relates to pliers that can be operated with one hand, comprising two pliers legs, which pivot in relation to one another about an engagement bolt when a force is applied, the pliers legs also overlapping one another in a crossover region, a pliers mouth being formed on one side of the crossover region of the pliers legs and grip portions being formed on the pliers legs on the opposite side, below the crossover region, the pliers legs also being connected by means of a control element and a spring drive, which pretensions the pliers mouth into an open position, which open position is attained automatically in a spring-loaded manner once the grip portions are released; moreover, in a first phase of movement of the spring drive, the pliers-mouth jaws moving toward one another and, in a second phase of movement, a catch of the engagement bolt engaging in a latching tooth formation, it being possible for a forced rotation of the movable pliers-mouth jaw to be carried out about the engagement bolt; the control element comprising two links that are connected to one another in the manner of a toggle lever by means of a toggle joint and, associated at least with one link, a spring being provided, which, while being supported on the links, pretensions the links into an extended position and, as a result, brings about, if appropriate, the disengagement of the movable pliers leg from the tooth formation and in any event the moving of the movable pliers leg into the greatest open position of the mouth by means of the spring drive created in this way.
Pliers of this kind that can be operated with one hand are known from WO 00/13856. The spring is formed there, FIG. 20, as a rotary leg spring and is associated with the links that are connected to one another in the manner of a toggle lever, mounted at the toggle-joint pin. The accommodating space is in this case formed by the U space of the links of the control element that are correspondingly folded in a U-shaped manner.